Mine

        /* USBCopy button trigger function */
        style = (IXP425_GPIO_IN|IXP425_GPIO_FALLING_EDGE);
        gpio_line_config(IXP425_GPIO_PIN_4, style);
        if (gpio_pin4_intr_enable == 0) {
                retval = request_irq(21, synobios_interrupt_gpio4, 0, "synobios", NULL);
        }

        /* USBCopy LED control, set initial state as NONE */
        fUSBCopyButtonOn = 0;
        style = IXP425_GPIO_OUT;
        gpio_line_config(IXP425_GPIO_PIN_4, style);
        gpio_line_set(IXP425_GPIO_PIN_4, 1);